What is the probability that, twelve seconds from a randomly selected starting time, a certain digital clock will display a number of seconds x such that x < 10 ?
(A) 19/60
(B) 3/10
(C) 1/5
(D) 11/60
(E) 1/6
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What is the probability that, twelve seconds from a randomly
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seandcarey
- Newbie | Next Rank: 10 Posts
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Important that the distinction of this question is that it is less than 10, not less than or equal to.
What seconds are less than 10?
0,1,2,3,4,5,6,7,8,9 so 10 choices. 10/60 or 1/6.
The answer is E.
The 12 seconds part of the question I believe to be deceptive. All you need to know the number less than 10, but if you want to think of it as your start time to get to 0 is XX:XX:48 seconds to XX:XX:57 seconds. Or 10 possible start times.
What seconds are less than 10?
0,1,2,3,4,5,6,7,8,9 so 10 choices. 10/60 or 1/6.
The answer is E.
The 12 seconds part of the question I believe to be deceptive. All you need to know the number less than 10, but if you want to think of it as your start time to get to 0 is XX:XX:48 seconds to XX:XX:57 seconds. Or 10 possible start times.
